See exactly when rain will start and stop with a minute-by-minute precipitation nowcast for the next hour.
17°
Clear
Feels Like: 15°
Min: 17°
Max: 29°
The next few hours will be clear, with today reaching 29°C and dropping to 15°C. The coming days will be mostly clear
Compare today's weather with yesterday's data and track temperature trends over time.
Hourly Forecast
Daylight Hours
06:55
Sunrise
19:09
Sunset
Moon
Waxing Crescent
11:45
Moonrise
20:52
Moonset
Daily Forecast
Today
Wednesday
Thursday
Friday
Saturday
Sunday
Monday
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Wednesday
Thursday
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UV Index
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Weather in Vacaville today, September 15, 2026
Conditions in Vacaville on September 15, 2026 favour clear skies, so the day opens with a fine, sunny outlook. Any interruptions to the blue should be brief rather than lasting. Morning skies stay relatively clear, holding cloud close to 0% near 07:00. The early part of the day favours being outside.
Temperatures climb from an overnight low near 17°C toward a daytime high of about 29°C. Relative humidity sits between 24% and 70%, reaching its peak around 22:00. Airflow remains manageable, reaching about 7.4 km/h around 22:00.
Through the afternoon skies look more workable, with cloud near 4% around 23:00. Later outdoor plans have a clearer window than the morning may have suggested. Horizontal visibility holds close to 16.1 km. Expect sunrise at 06:55, sunset at 19:09, and 12 hours 14 minutes of sunlight today overall.
Overall, Vacaville on September 15, 2026 favours outdoor plans under mostly open skies, with a comfortable high near 29°C.
Frequently asked questions about weather in Vacaville
How warm does it get in Vacaville?
The warmest month in Vacaville is August, with average high temperatures of 31°C. The average temperature during this period is around 22°C.
How cold does it get in Vacaville?
The coldest month in Vacaville is December, with average low temperatures of 6°C. The average temperature during this period is around 10°C.
What is the wettest time of year in Vacaville?
The wettest month in Vacaville is January, with an average of 126mm of precipitation.
What is the driest time of year in Vacaville?
The driest month in Vacaville is August, with an average of 0mm of precipitation.
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